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Showing content with the highest reputation on 08/05/16 in all areas

  1. 24 points
    Just another day at the office in Colorado for Netweather, only scored 4 tornadoes today but some were very pleasing on the eye and others have insane video footage. Target was Fort Morgan to Sterling. Got onto the first Tornado Warned storm near Wiggins and watched it rip up a few trees and throw farm machinery across the road near us and a nasty tumble weed cut Sir Tom Lynch's arm. After that we left that storm whilst it was still tornado warned and blasted east towards Wray where a pair of Supercells were starting to get interesting and near Eckley we watched a stunning white elephants trunk tornado just to our North. The last Supercell in the line just to our south east started to drop golfball hail on us so we let the core pass and went under the base of this stunning LP Supercell. Just near Wray our 3rd Tornado briefly touched down and then the best of the day touched down 2 miles North of Wray which was the star of the show. Will put a few pictures up here but the others have incredible video footage to show you all. Staying in Colby overnight big day tomorrow. Best Paul S & Team 1
  2. 5 points
  3. 4 points
    What you need to appreciate is that just because there is a relatively high PWAT flow of air, this is not in my view a true 'plume'. A true plume in the sense we discuss originates from a precise area of Iberia, nice firm dry lid of air over warm and humid air leading to significant instability. This is not what we have here in my view, nor is it even THAT humid - to me it is very warm, but in no way resembles a 'thundery plume'. Looking at the mid levels, on the Kent coast at least, it reminds of a nice Spanish late spring day - I'm not seeing any sign of instability at all (not that I'm located in a hot spot to be fair). For the last few days I have been reluctant about the coverage of storms and have always favoured isolated outbreaks across Midlands/Wales/NW England...based on how yesterday played, the atmosphere is probably less unstable than the models would suggest and therefore I favour the reserved positions being taken. So...sorry William, but on Mapantz' side of the fence and thinking lightning coverage will be lower than we may have thought early/mid week. On the plus side, with increases in frontal/trough features in the coming days, together with a fall in pressure, lightning coverage will increase. But, it will be a full on case of now casting as it is clear both the MetO and Beeb are very unsure as to the timing of fronts and troughs and therefore whether storms will be likely, where, when etc. If the conditions fall nicely, ie a period of surface heating, nice build of instability, with a front/trough engaging at the right time, a decent thunderstorm or two could be possible. BUT, as I allude to, the whats, whys and wherefores are all up in the air. Be glad, our true season hasn't even yet started so anything is a bonus (historically, late May is the period where true plumes with viable imports which both the SE and SW often rely on, become viable)
  4. 3 points
  5. 3 points
    Looking forward to seeing the videos and reports from the home team. Meantime, if its OK to post here, a super video on the Keraunos site. http://www.keraunos.org/actualites/fil-infos/2016/mai/tornade-wray-colorado-7-mai-2016-etats-unis-tornado
  6. 3 points
    Yesterday's lightning strikes - not a bad start to the season!
  7. 3 points
    Apparently it's 26C in Bexley at the moment! so at 11:10 it's already the hottest day of the year so far. Just wonder if the hotter than expected temperatures will be enough to pop the atmosphere.
  8. 3 points
    Forecast for today (Sunday) Some models are showing no precipitation for today, others are. Personally, I think something will trigger at some point during the afternoon, and when it does it could potentially be stronger than last night's storms due to higher energy, temperatures, lapse rates and a greater swathe of richer Theta-W air mass covering a larger portion of the country. Unlike today, convection initiation locations won't be as easy to pick out, and instead any convection that does manage to form is likely to be more scattered in nature with just about anywhere in the risk zones able to see something. Like today, however, the North West of England and Northern Wales seem to be best placed when it comes to parameters pulling together to favour storms.
  9. 3 points
    Irrespective of weather preferences, its a classic highly amplified Spring pattern with cold northerlies alternating with warm southerlies. Many people point to this being a feature of Spring's following a strong El Nino winter. Its partly due to the fact that traditionally both sides of the ENSO coin, Nino or Nina, feature a waning process at this time of year - and it is the ying-yang effects of the atmospheric circulation as a result of these processes that give rise to sudden flips in weather patterns, at the same time as thermal differential gradients between the poles and mid-latitudes realign themselves in the transition between winter and summer The last update discussed the possible longevity of the unseasonal cold spell lining up to commence from the last week of April. The considerations in terms of this were attached to the duration and extent of an attempted dip in atmospheric angular momentum (AAM) tied to the preliminary winds of change blowing across the Pacific Ocean that are set to very gradually, and uncertainly, tug the global atmospheric circulation towards a deceleration in globally averaged wind flow as indicative of the end of El Nino - and ever increasing chances of La Nina influence thereafter on global weather patterns through the second half of the year In simple terms this adds up to reduced upstream jet velocity, and as a consequence, growing sequences of retrogressive global upper air patterns seasonally across the hemisphere. But, in between these increasing frequency retrogressive phases over time, systematically weakening rebounds of the atmospheric circulation to current default Nino signature continue still likely to occur in the shorter term, which, for late Spring and early Summer in our parish, hold the hopes for settled and warm conditions. Disclaimer: Relating here to a transitional weak/neutral ENSO signal, so comparisons and associated attempts at working assumptions made with the evolving rapidly strengthening Nino to exceptional levels 12 months back, and the unsettled UK summer that followed, are not valid. We should remember that a hot Nino type summer did actually occur in 2015 - it was simply too far east of the UK due to the strength of the Pacific westerlies coming from upstream interacting with cold Atlantic SST's With the summer-time polar easterly regime now established, each dip in AAM suggests a westward pull upstream (and then working downstream) of the upper air patterns and encourages pressure rises to our north, backing westwards as the pattern retrogresses. Each bounce back in AAM again thereafter adjusts the upper air pattern back eastwards, at this time of year helping to shift the jet stream northwards and consequently assisting warm air advection from the south. The results, evolving with time, according to natural seasonal wavelength changes. In describing this tug o' war process on the atmospheric circulation, we get an illustration of how the weather pattern flips, that were referred to at the start of the post, come about. So we can think of the mid April to early May sequence as one of those initial retrogressions of the pattern which, as far as our Atlantic sector is concerned, saw our trough into Scandinavia develop at the same time as downwelling polar easterlies ( legacy of the stratospheric vortex final warming)) augmented further the blocking arrangement to our NW and Greenland. The retrogression of the whole pattern then shifted the Scandinavian trough back westwards, but, as this was happening, a bounce back in AAM saw a shift northwards of the jet stream, the pattern shunted back eastwards again, with the emergence of mid latitude ridging taking up residency and re-amplifying this time to our east, to pave the way to this weeks highly welcomed sharp recovery in temperature and much more seasonally settled and warm weather Phase 8/0 of the Global Wind Oscillation, as predicted in the last post, denoted the bottom-out limit to the last dip in angular momentum. Its register on the upper air pattern was reflected by the late April cold spell from the arctic. The return of the Global Wind Oscillation, also as suggested in the last post, to Phases 5/6/7 depicts the relative recovery in angular momentum and the volte face to a warm seasonal late Spring pattern and warm air advection from the south. If anything this flip has happened sooner than seemed possible just before the arctic spell - so that gives us a feel that for the time being at least, irrespective of the changes in the Pacific Ocean - the atmosphere is still fully receptive to defaulting to a weakening Nino state In this respect, the GEFS forecasts look strikingly familiar to the last updated post. We are back to exactly where we were about three weeks back in terms of the atmospheric state - with the models teeing up yet another retrogression of the pattern in the D5-7 period as the Global Wind Oscillation looks set for another return through Phase 8/0 (NB don't take the current GEFS forecast too literally). These phases represent the transitional ENSO zone between Nino and Nina, and are a symptom of the continuation of the pre-cursor process of the last vestiges of warmth disappearing from the western Nino zones in the Pacific and the colder sub surface waters already evident surfacing off the coast of Peru - and being edged westwards by the stirrings of easterly trade winds which will increasingly be propagated north and eastwards from the Indian Ocean as more and more time progresses. With this prognosis in mind, I've little doubt that the GEFS forecasts will continue to predict their over-bias orbit for Nina-like Phases 1/2 right to the time it actually happens - which looks probable eventually based on the direction of travel of the ocean/atmosphere relationship. Its a case of how long they may stay de-coupled as the transition continues. It is the uncertainties of this relationship in the coming weeks and couple of months that will determine what type of high summer we will get. In such a tricky transition as we have in terms of speed, timing and evolution of change, its difficult to know and provide confident answers to this. Seasonal models underpin this uncertainty. But then (fortunately) I don't attempt seasonal forecasts, and instead enjoy watching the process evolve down to 2 to 4 week period ahead instead. With that time period in mind looking ahead for the rest of the month, the last post suggested we should look out for further programmed rises of heights to our NW during May as part of the retrogressive sequences discussed. So we should not be too surprised by a rinse and repeat of the April > May general pattern in the coming few weeks to take us into the beginning of June. The computer models are coming together to suggest exactly that happening. There are simply differences at this stage in terms of placement of the Euro trough to the east which determines any attempted cold(er) air advection - following the humid warmth of the coming week. The latest ECM Dutch ensembles this morning give a clear signal of the extent of the current continental warmth, and the distinct drop in temperature that may occur to our east by next weekend as the next programmed retrogression occurs Also, the suggested marked change in dew-points in these ensembles shows clearly the contrasts of the characters of the humid air-mass from the south set to dominate through this week, and the arctic origins of the air-mass predicted to follow yet again from the north Here in the UK, we might yet be hopeful to miss the coldest uppers - with the trough sufficiently far enough east of us. Unless it retrogresses yet again as it did in late April. Frost looks like it might yet have another belated word, with more chilly nights to come. With the bigger picture discussion in mind from above, its reasonable enough at this stage to expect another settling down of the pattern from the south west to follow any cooler/colder incursion sometime during the last week or so of the month, with another potential warm up - more particularly in the south. The extended 10 to 15 day ensembles already are already supporting the bigger picture hypothesis, hinting at something of a subsequent slow recovery of temperature in the Netherlands - so, being further west, we might reasonably expect to see that faster in the UK. Albeit likely courtesy of a switch to westerly atlantic based influence to follow the northerly which might leave NW parts most susceptible to any weather fronts Enough though already. Before any of that happens, the best thing to do right now is take Frosty's advice and enjoy the lovely warm summer-like conditions we have this weekend that are set to last throughout the week - between some thundery rain edging northwards from the slowly eastwards migrating trough over mainland Europe to affect the south, more especially at first
  10. 2 points
  11. 2 points
    24'c here, 2'c above what was forecasted! Nice cumulus up to my NW!
  12. 2 points
    I believe it is too, it's been around for a few days - still haven't got used to it... quick glance and I think *yay*, two seconds later, "Oh, anaprop" *glum face*.
  13. 2 points
    I'm ruling nothing out, William, I'm no authority on weather. I have however closely watched thundery events for the last 12 years (and enjoyed them for longer than that) and have seen FAR FAR better setups produce nothing - on balance of probabilities I'm just trying to shape expectations, certainly not telling you or anyone else there won't be thunder either today or beyond.
  14. 2 points
    Sun burnt face is beginning to peel off
  15. 2 points
    The Gfs 6z op shows temperatures taking quite a nose dive next weekend with a much cooler Northerly airflow although it becomes mainly dry with sunny spells and just the odd light shower brushing east coastal areas but cold enough inland briefly for overnight frosts, however, the northerly is soon cut off by high pressure building in from the sw / w and temperatures rise to pleasantly warm levels during the following week. In the meantime, enjoy the current warmth which today is at it's peak with mid 20's celsius although it stays on the warm side for most of the week ahead with temps into the high teens / low twenties celsius, some rain around during the week ahead, mainly across southern UK, heavy and thundery in places but largely fine further north but it does look like a change from the north by next Fri / Sat.
  16. 2 points
    Wouldn't suprise me your in Lincoln after all.
  17. 2 points
    The recordings of the stream from overnight are processing at the moment, I'll try to edit some highlights together later when they're done.
  18. 2 points
    Didn't think you'd be interested in commenting on my post, so I'm overwhelmed that you think my post was good quality, thanks very much! To be honest, it's more Altocumulus cloud now rather than Altocumulus Castellanus, so not sure what risk there is today but it certainly does look better as you've said. We shall have to see.
  19. 2 points
    I was genuinely surprised that the stuff near you late last night didn't give a light show....intense echoes on the radar...here's a screenshot from said time courtesy of NWx
  20. 2 points
    HERE IS MY LATEST ANALYSIS USING DATA SUPPLIED BY THE NWP OUTPUT COVERING 5 OF THE WORLDS MOST POWERFUL WEATHER COMPUTERS ISSUED AT 09:00 ON SUNDAY MAY 8TH 2016 THE CURRENT GENERAL SITUATION Low pressure over Spain and later France will push troughs up across Southern Britain over the coming days in a warm and moist Easterly flow. The North will be largely set fair in the same Easterly flow though here the air will be more stable than in areas further South. http://www.wetterzentrale.de/pics/Rtavn001.gif CURRENT SNOW FORECAST AND/OR FREEZING LEVEL OVER THE UK The UK continues to see the freezing level across the UK range between 8000-10000ft over the following three or four days and these levels will extend to the far NW too today where values have been rather lower than elsewhere across the UK recently. http://www.snow-forecast.com/maps/dynamic/uk http://www.natice.noaa.gov/pub/ims/ims_gif/DATA/cursnow.gif MODELS-2 WEEK HEADLINE Rather warm with thundery showers in the South. Perhaps rather cooler later. THE GFS JET STREAM FORECAST The Jet Stream's main core is situated well South of the UK near Southern Spain and North Africa in association with a large depression down there. This remains for much of this before a rise in pressure over the Eastern Atlantic pushes a thread of the flow South across the UK in a Northerly flow. Then late in the period a rather complex Jet stream pattern emerges with the main energy still wanting to lie to the South of the UK rather than elsewhere. http://www.netweather.tv/index.cgi?action=jetstream GFS OPERATIONAL The GFS Operational Run today shows Low pressure down to the South and later to the SE of the UK this week with Easterly winds and showery weather for many Southern areas with rather warm and in places humid conditions prevailing. In the North it will stay largely dry and this will extend to Western areas further South towards next weekend as the Low to the South moves East and winds back to a cooler Northerly though with further heavy showers across Southern and later Eastern areas of the UK. Then through the second week details look elusive but in essence the UK looks to remain close to showery Low pressure with some bright and sunny intervals in between but with temperatures more likely to have returned to normal values by then at the same time as being less humid as winds back more to a Westerly at times. http://www.wetterzentrale.de/pics/Rtavn1441.gif http://www.wetterzentrale.de/pics/Rtavn3841.gif NEW GFS PARALLEL RUN Using the GFS Operational Run above as a template for the coming two weeks the GFS Parallel Run today differs in that higher pressure is shown to extend East into the UK next weekend with a fine and bright spell lasting for several days and perhaps longer across the South before a return to unsettled and possibly windy conditions spreads down across all areas later, this time from the NW with temperatures after a warm start reverting to nearer to average values. http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=144&mode=0&runpara=1 http://www.meteociel.fr/modeles/gfse_cartes.php?&ech=384&mode=0&runpara=1 GFS CONTROL RUN This run follows closer to the Operational rather than the Parallel Run through the phase surrounding next weekend and the start of the second week with continues showery conditions in winds from a cooler Northerly source. However, late in the period this run shows warm and sunny conditions developing across England and Wales as the Azores High extends NE into Southern Britain with any wind and rain held across the far NW. http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=144&mode=0&carte=0 http://www.meteociel.fr/modeles/gefs_cartes.php?code=0&ech=384&mode=0&carte=0 GFS ENSEMBLE DAY 14 DATA The clustering today for day 14 remains distinctly useless as a tool into what conditions will be like over the UK in two weeks time with an equal split of both Low and High pressure scenarios on offer meaning everything from potentially dry and sunny weather to cool and showery conditions in a Northerly flow. http://www.weatheronline.co.uk/cgi-bin/expertcharts?LANG=en&MENU=0000000000&CONT=euro&MODELL=gefs&MODELLTYP=2&BASE=-&VAR=cpre&HH=372&ZOOM=0&ARCHIV=0&RES=0&WMO=&PERIOD= UKMO The UKMO model this morning shows the thundery Low pressure area currently over Spain dominant across Southern and later Eastern areas of the UK throughout this coming week as it slowly trundles it's way East to lie over SE Europe by next weekend with contrasting High pressure centred up to the NW of the British Isles by then resulting in a fall off in temperatures under the Northerly or NE'ly aspect to the flow by then with many North-western areas of the UK having an entirely dry and warm week while the South and East see further heavy showers at times right out to and probably including next weekend. http://www.wetterzentrale.de/pics/Rukm1441.gif THE FAX CHARTS The Fax Charts show quite a complex scenario revolving around the movement of Low pressure over Spain and it's effects on the UK. The basic message is for the NW to see the best conditions with fronts moving into the South at times with some heavy and thundery rain in humid conditions until later in the week when an attack of fronts from the North looks like reducing temperatures to average with the risk of further showers at times in winds becoming more from the North by next weekend lowering the humidity values. http://www.weathercharts.org/ukmomslp.htm#t120 GEM GEM this morning shows slow but subtle changes in it's patterning over the next week to 10 days as the current warm and humid SE flow backs away towards the NE and later North with the showery conditions across the South and East too later this week breaking down under High pressure inching in from the West by next weekend with fine and less warm conditions for all for several days before High pressure to the WSW sets up a WNW flow across the UK with rather more unsettled conditions affecting the North and NE late in the run with the SW seeing the driest and warmest conditions by then. http://www.wetterzentrale.de/pics/Rgem2401.gif NAVGEM NAVGEM today also shows the slow decline in conditions from the South affecting the UK as winds back more towards the NE and North through the coming week. However, thundery showers will affect many Southern and Eastern areas for a good few days yet and it will feel warm in any sunshine. Then by next weekend a cooler North flow and showers transferring towards the East will spell a slow change to a more Atlantic based west or NW pattern by the start of the second week. http://www.wetterzentrale.de/pics/Rnvg1681.gif ECM ECM today also shows High pressure inching in from the West next weekend and into the second week but it never quite makes it maintaining something of a Northerly drift down across the UK with perhaps a few showers still in the East and more importantly cleaning up the air into a cooler fresher feel. As we approach the end of the run it shows more instability being injected into the air across the UK with showers returning to all this time from the NW. http://www.wetterzentrale.de/pics/Recm2401.gif ECM 10 DAY MEAN (12z) Last nights 10 day Mean Chart has backed a ridge West from earlier versions of this chart which leads me to believe that any advancement of High pressure into the UK from the West from next weekend will be slow, painstaking or at worst non-existent...more runs needed. http://www.wetterzentrale.de/pics/Reem2401.gif NOTABLE TRENDS & CHANGES FROM PREVIOUS RUNS The theme remains for a warm and humid period of weather across the UK before a gradual reduction in both temperatures and showers look likely later though conditions beyond next weekend still come with low confidence. 31 DAY HISTORICAL VERIFICATION STATS FOR GFS, UKMO & ECM The verification Statistics of GFS, UKMO and ECM show at 24 hours ECM ahead at 99.6 pts with UKMO at 99.4 pts and GFS at 99.2 pts. At 3 days ECM is leading with 97.1 pts to UKMO's 96.2 pts while GFS lags behind at 95.5 pts. At 5 days ECM leads with 88.3 pts to UKMO at 86.5pts and GFS at 83.2 pts. Then at 8 Days ECM has the leading spot from GFS with 61.2 pts to 51.3 pts. Finally at Day 10 ECM has the lead from GFS with a score of 44.5 pts to 36.2 pts. http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day1_PMSL_MSL_G2NHX.png http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day3_PMSL_MSL_G2NHX.png http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day5_PMSL_MSL_G2NHX.png http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day8_PMSL_MSL_G2NHX.png http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/allmodel/daily/cor/cor_day10_PMSL_MSL_G2NHX.png MY THOUGHTS Although the overall patterning of the weather over the next week looks pretty much set in stone the method and in particular local detail that gets us out of this pattern for the period surrounding next weekend and beyond remains very uncertain. So step by step what we have now is Low pressure down over Spain and Portugal which incidentally is giving some pretty inclement May weather down there and some of this is heading up towards Southern Britain to affect these areas between tomorrow and Wednesday. The warm and humid feed of air surrounding this will affect much of the UK but the North looks like getting away with a largely dry spell over the coming 3-4 days with the highest temperatures to the NW. Then as the week progresses the trend will be for winds to back away from the SE to more of a NEy feed by the end of the working week lowering both temperature and humidity values somewhat while maintaining some showery weather to include eastern areas too by that time. It's from then that the confusion between the models start as colder air will be moving South across Scandinavia and with High pressure to the West and NW of the UK this could be driven our way with the models in total disarray about how much of that cold and showery air will affect conditions over the UK. Some output suggests not much while others maintain a cooler Northerly drift with further showers eventually culminating in further unsettled weather fed down from the NW with rain and showers at times to end the forecast period. However, this is not the only option with other output suggesting High pressure ridging towards the South and setting up more of a NW/SE split at least for a time with the SE half of the UK becoming warm and dry with rain and wind towards the NW. It will be interesting to see how the models handle the changes through the coming week as all options shown look to me totally feasible. However, to end with the more definitive part of the forecast it looks a showery week to come especially across the South and East where they could be heavy and thundery at times. The best weather looks to be towards the NW this week and after a very warm start for some the conditions look set to turn rather cooler by next weekend with temperatures closer to the seasonal average at the same time as feeling less humid. Next Update Monday May 9th 2016 from 09:00
  21. 2 points
    Not sure if this is relevant to what you were saying stainesbloke, but the amount of (high level?) cloud & lack of totally clear sky nowadays has been studied by the scientific community. There seems to be plenty of findings that suggests the increase in aircraft contrails are causing more high level cloud. And it appears to be very relevant to our Region because of the amount of aircraft movements over us. Scientists now admit that emissions from aircraft are forming artificial clouds that block out the sun.... Reading University’s Professor Keith Shine, an expert in clouds, said that those formed by aircraft fumes could linger ‘for hours’, depriving those areas under busy flight paths, such as London and the Home Counties, of summer sunshine. Experts have warned that, as a result, the amount of sunlight hitting the ground could be reduced by as much as ten per cent. Over the busiest areas in London and the South of England, this high-level cloud could cover the sky, turning bright sunshine into hazy conditions for the entire area. If you click through the 7 satellite images on this BBC webpage "How aircraft contrails form clouds", you can see an example that happened on that particular day. It looks like the military performed some airobatics (circles) out in the North Sea that resulted in cloud for the west of our Region later that day: http://news.bbc.co.uk/1/hi/sci/tech/8309629.stm And even remote parts of the planet are impacted. This report on the impact in Alaska: http://link.springer.com/article/10.1007%2Fs007040170045#page-1 Anyway.... sorry about all that boring serious stuff.... beautiful day out there. I've invited the neighbours around for a bbq later. Just hoping the breeze doesn't get up and blow smoke and ash everywhere!!
  22. 2 points
    This cooler spell is looking nothing like the previous cold spell we had the other week thankfully- areas to the north of us have warmed up significantly over the past week or so and the uppers don't look nearly as cool for most of us. In the meantime let's enjoy this fantastic summery spell.
  23. 2 points
    Autumn has been very warm and dry in Christchurch and many parts of NZ. Most days have been over 20C since March and the start of May actually became warmer than the end to April with temperature maxima of 23-24-23-23-15-22-21 for the first 8 days of May and the mean temperature for the airport running roughly 5C above average! There has been no rain in Christchurch for 3 weeks and only 8mm in the last month. Looks set to continue, as what was looking like a strong southerly this week is being flattened out into continued strong northwesterlies which will make Canterbury warm and dry. The west coast will get a soaking however.
  24. 2 points
  25. 2 points
    Since when did you become the self-appointed spokesperson for 'most people'?
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